Download Bock Audio 407 User`s manual - Studiocare Professional Audio

User's manual
Bock Audio model 4-0-7
1) description
2) additional circuit notes
3) getting started
4) power supply and cable
4) safety warnings
5) specifications
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1) The Bock Audio model 4-0-7 is a high quality cardioid directivity studio condenser microphone
utilizing vacuum tube electronics. Utilizing the U47 format, originally built in the 1950's, this mic takes
that platform and expands the electronics bandwidth. It utilizes it's own proprietary cable and power
supply. The microphone's audio output is standard male XLR3, with positive excitation of the
diaphragm at the front of the mic resulting in a positive voltage at the output XLR's pin 2. Audio output
is fully transformer balanced.
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2) The Bock Audio 407 uses classic pentode run as single triode circuitry with no additional negative
feedback and high quality through hole components. Through hole components are more mechanically
robust than surface mount and allow for worldwide ease of repair. Single triode mic circuits demand
excellent capsules before them and excellent transformers after them, with a reward of low noise,
simplicity of troubleshooting, and classic sound unachievable otherwise. The Bock 407 departs from
the classic U47 of the 1950's in it's expansion of the bandwidth of the electronics, which has had it's
low frequency cutoff frequency decreased from 40Hz to 10Hz, without any loss of high frequencies, by
use of a larger value grid resistor.
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3) It is recommended that the user place the mic in it's shockmount on a stand and connect all the
cables before applying power to the unit. Allow a few minutes for the mic to warm up.
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4) The Bock Audio IFET is powered by P48 phantom power.
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5) CAUTION: Shock Hazard: Do not open microphone when connected to power source. No user
serviceable parts inside. Refer failed units to qualified service personnel.
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VORTICHT: Shock gefar: Bitte nicht daf mikrofon offen wenn es eingeschaltet ist einen stoppkontakt.
Keine zu wartenden Teile im Inneren. Beziehen gescheitert Einheiten qualifiziertem Service-Personal.
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ATTENCIONE: Choc hazard: N'ouvrez pas le microphone quand il y a un connectionne avec un source
d'electricity. Aucune pièce réparable par l'utilisateur. Référer unités échoué à un personnel qualifié.
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ATTEZIONE: Riscchio di scossa: Non aprire il microfono quando e attacato al'eletricita. Non contiene
parti riparabili. Riferimento unità riusciti a personale qualificato.
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www.bockaudio.com
818-506-1870
Specifications:
Patterns:
Frequency Range:
Sensitivity:
Equivalent Noise:
Distortion vs.SPL @1kHz:
Impedance:
Recommended load:
Dynamic range
(maxSPL-"A"noise):
S/N (94dB-noise):
Capsule size:
Tube type:
Dimensions:
Weight:
Shipping weight:
Power Supply:
www.bockaudio.com
Cardioid
10Hz to 18kHz, +/-2dB
26mv/Pa
18dB (“A” weighted) 32dB (unweighted)
112dB = 0.5% THD
118dB = 1% THD
129dB = 2% THD
(increasing distortion is non-exponential, nearly linear, and
primarily 2nd harmonic)
200 Ohms true transformer balanced
2k Ohms
94dB
76dB “A”, 62dB unweighted
1” diameter, single backplate K47 type
New Old Stock EF814k
2” dia x 8.5” oal (52x216mm)
1lb 9.3oz (1.58lbs) =716g
13 lbs
N470 true linear, factory wired 115v or 230v operation
818-506-1870